1. Field of the Invention
The present invention relates to a display method for carrying out scissoring-processing of a stroke letter with a high speed window-display thereof.
2. Description of the Related Art
In recent years, a CAD (Computer Aided Design) system has been developed and is in the improvement stage for practical application. CAD centers on the multifarious design services in the electrical and mechanical manufacturing industries and its field of application is spreading.
In general, the CAD system is constituted by a host computer, a graphic display unit, a plotter and various input devices, and a basic software for activating these devices.
The CAD system is often used to output a character or letter formed by stroke data, that is, a stroke character or letter to a graphic display unit, thus displaying many kinds of information.
On the other hand, when a graphic form is displayed on a screen of a display unit, if the original graphic form is large, it is required to adapt a display method such that a range contained in the display screen is cut out, or a window is provided in a part of the display screen and a partial graphic form is cut out within the window.
A processing which cuts out a portion limited by a predetermined frame is referred to as scissoring processing and is generally used in the CAD system.
Means for interacting between a user and a system, that is, a man-machine-interface is regarded as of major importance nowadays in the CAD system. It is advisable to provide a technique to carry out the interaction more speedily and smoothly, and process a series of stroke letters very fast by scissoring to display a limited portion of a display on a graphic display unit.
In the prior art CAD system, when a stroke letter line is displayed, the series of stroke letters is regarded as a set of segments, and scissoring processing effects each segment, forming a series of letters. Then, displaying of the limited portion of the display is done.
Nevertheless, in the above conventional system, since a series of stroke letters is regarded only as a set of segments, there is a problem that scissoring processing must be carried out on each line segment forming a series of letters, and it takes an enormous amount of time to carry out this process.
In light of the above circumstances, the present invention has been devised.